Replace alpine packages with data.forgejo.org/oci/alpine latest (#1490)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| code.forgejo.org/oci/alpine → data.forgejo.org/oci/alpine | container | replacement | `latest` → `latest` |
| [code.forgejo.org/oci/alpine](https://hub.docker.com/_/alpine) ([source](https://github.com/alpinelinux/docker-alpine)) → [data.forgejo.org/oci/alpine](https://hub.docker.com/_/alpine) | container | replacement | `3.21` → `3.21` |
| code.forgejo.org/oci/alpine → data.forgejo.org/oci/alpine |  | replacement | `latest` → `latest` |

This is a special PR that replaces `code.forgejo.org/oci/alpine` with the community suggested minimal stable replacement version.

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Reviewed-on: https://code.forgejo.org/forgejo/end-to-end/pulls/1490
Reviewed-by: Mathieu Fenniak <mfenniak@noreply.code.forgejo.org>
Co-authored-by: Renovate Bot <bot@kriese.eu>
Co-committed-by: Renovate Bot <bot@kriese.eu>

actions/example-container/.forgejo/workflows/test.yml

@@ -3,6 +3,6 @@ jobs:
   test:
     runs-on: docker
     container:
-      image: code.forgejo.org/oci/alpine:3.21
+      image: data.forgejo.org/oci/alpine:3.21
     steps:
       - run: grep Alpine /etc/os-release

actions/example-shell/.forgejo/workflows/test.yml

@@ -25,7 +25,7 @@ jobs:
     needs: [sh-fallback]
     runs-on: docker
     container:
-      image: code.forgejo.org/oci/alpine:latest
+      image: data.forgejo.org/oci/alpine:latest
     steps:
       - name: default is bash but with a fallback to sh in case it does not exist
         run: |

federation/scenario-mastodon/compose.yaml

@@ -5,7 +5,7 @@ networks:
 
 services:
     forgejo:
-        image: code.forgejo.org/oci/alpine:latest
+        image: data.forgejo.org/oci/alpine:latest
         volumes:
             - ./forgejo/certs/:/usr/local/share/ca-certificates/
             - ./forgejo/init/:/init/